/* ==========================================================================
   Tokens
   ========================================================================== */

:root {
  --paper: #f7f6f2;
  --surface: #fdfcf9;
  --ink: #1c1b19;
  --text: #3a3833;
  --muted: #6d6a63;
  --faint: #a8a49b;
  --line: #e4e0d6;
  --accent: #c2410c;
  --dot: rgb(28 27 25 / 0.07);

  --font-sans: "Geist", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: "Geist Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --font-serif: "Instrument Serif", Georgia, serif;

  --sidebar: 22.25rem;
  --gutter: 4rem;
  --when: 7.125rem; /* width of the date column in timelines */
  --ease: cubic-bezier(0.2, 0.7, 0.2, 1);

  color-scheme: light;
}

:root[data-theme="dark"] {
  --paper: #111110;
  --surface: #191917;
  --ink: #eeece6;
  --text: #cfccc4;
  --muted: #98948b;
  --faint: #5f5c56;
  --line: #2a2926;
  --accent: #ff7a3d;
  --dot: rgb(238 236 230 / 0.06);

  color-scheme: dark;
}

/* ==========================================================================
   Base
   ========================================================================== */

*,
*::before,
*::after {
  box-sizing: border-box;
}

/* Sizes are in rem, so this one value scales the whole desktop layout (text, spacing, photo).
   Phones set their own size in the small-screen section below. */
html {
  font-size: 84.375%;
  scroll-behavior: smooth;
  scroll-padding-top: 24px;
}

body {
  margin: 0;
  background-color: var(--paper);
  background-image: radial-gradient(var(--dot) 1px, transparent 1.25px);
  background-size: 1.375rem 1.375rem;
  color: var(--text);
  font: 1.125rem/1.65 var(--font-sans);
  -webkit-font-smoothing: antialiased;
  transition: background-color 0.3s, color 0.3s;
}

a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--accent) 40%, transparent);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color 0.2s, text-decoration-color 0.2s;
}

a:hover {
  color: var(--accent);
  text-decoration-color: currentColor;
}

strong {
  color: var(--ink);
  font-weight: 600;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection {
  background: color-mix(in srgb, var(--accent) 22%, transparent);
}

img {
  user-select: none;
}

[hidden] {
  display: none !important;
}

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(14px);
  }
}

/* ==========================================================================
   Layout: sticky sidebar + content column
   ========================================================================== */

.layout {
  display: grid;
  grid-template-columns: var(--sidebar) minmax(0, 1fr);
  max-width: 80rem;
  margin-inline: auto;
}

.content {
  max-width: 57.75rem;
  padding: 4rem var(--gutter) 0;
}

/* ---------- Sidebar ---------- */

.sidebar {
  position: sticky;
  top: 0;
  display: flex;
  flex-direction: column;
  height: 100vh;
  height: 100dvh;
  overflow-y: auto;
  padding: clamp(1.75rem, 7vh, 3.5rem) 2.25rem 1.75rem 2.625rem;
  border-right: 1px solid var(--line);
}

.sidebar > *,
.bio {
  animation: rise 0.8s var(--ease) both;
}

.sidebar > :nth-child(2) { animation-delay: 0.06s; }
.sidebar > :nth-child(3) { animation-delay: 0.12s; }
.bio { animation-delay: 0.18s; }

/* The sketch blends into the page like ink on paper, and glows softly in dark mode. */
.portrait {
  width: min(15rem, 30vh);
  margin: 0 0 0.25rem -1.125rem; /* optically align the faded edge with the text */
  mask-image: radial-gradient(closest-side, #000 60%, transparent);
  mix-blend-mode: multiply;
}

.portrait img {
  display: block;
  width: 100%;
  height: auto;
}

[data-theme="dark"] .portrait {
  filter: brightness(0.85);
  mix-blend-mode: normal;
}

.name {
  margin: 0 0 clamp(1.125rem, 4vh, 2rem);
  color: var(--ink);
  font: 400 2.875rem/1 var(--font-serif);
  letter-spacing: -0.01em;
}

.name > span {
  display: block;
}

.name > span + span {
  font-style: italic;
}

.profile-links {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: clamp(0.5rem, 1.5vh, 0.75rem);
  margin: 0;
  padding: 0;
  list-style: none;
}

.profile-links a {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  color: var(--text);
  font-size: 1.125rem;
  text-decoration: none;
}

.profile-links a:hover {
  color: var(--accent);
}

.profile-links i {
  width: 1.125rem;
  color: var(--muted);
  font-size: 1.125rem;
  text-align: center;
  transition: color 0.2s;
}

.profile-links a:hover i {
  color: inherit;
}

.theme-toggle {
  display: grid;
  place-items: center;
  flex-shrink: 0;
  width: 2.25rem;
  height: 2.25rem;
  margin-top: auto;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: var(--surface);
  color: var(--muted);
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s, transform 0.4s var(--ease);
}

.theme-toggle:hover {
  color: var(--ink);
  border-color: var(--ink);
  transform: rotate(-20deg);
}

.theme-toggle .fa-sun,
[data-theme="dark"] .theme-toggle .fa-moon {
  display: none;
}

[data-theme="dark"] .theme-toggle .fa-sun {
  display: block;
}

/* ---------- Footer ---------- */

.site-footer {
  margin-top: 1.75rem;
  padding-block: 1.5rem 3.125rem;
  border-top: 1px solid var(--line);
  color: var(--faint);
  font: 0.8125rem/1.6 var(--font-mono);
}

.site-footer a {
  color: var(--muted);
}

.site-footer a:hover {
  color: var(--accent);
}

/* ==========================================================================
   Content
   ========================================================================== */

.bio p {
  margin: 0 0 1rem;
  font-size: 1.25rem;
  line-height: 1.7;
}

.section {
  padding-block: 2.25rem;
}

.section-title {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin: 0 0 1.125rem;
  color: var(--ink);
  font: 400 2.375rem/1.1 var(--font-serif);
}

.section-title::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--line);
}

.reveal {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- Timeline (news, education) ---------- */

.timeline {
  margin: 0;
  padding: 0;
  list-style: none;
}

.timeline-item {
  display: grid;
  grid-template-columns: var(--when) 1fr;
  gap: 1.375rem;
  padding-block: 0.75rem;
  border-top: 1px solid var(--line);
  font-size: 1.1875rem;
}

.timeline-item:first-child {
  border-top-color: transparent;
}

.collapse .timeline-item:first-child {
  border-top-color: var(--line);
}

.timeline-when {
  padding-top: 0.1875rem;
  color: var(--muted);
  font: 500 0.875rem/1.6 var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.timeline-detail {
  color: var(--muted);
  font-size: 1.0625rem;
}

.text-button {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 0.5rem;
  margin-left: calc(var(--when) + 1.375rem);
  padding: 0.25rem 0;
  border: 0;
  background: none;
  color: var(--muted);
  font: 500 0.8125rem/1 var(--font-mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  cursor: pointer;
}

.text-button:hover {
  color: var(--accent);
}

/* ---------- Disclosure ---------- */

.collapse {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.35s var(--ease);
}

.collapse.is-open {
  grid-template-rows: 1fr;
}

.collapse > * {
  min-height: 0;
  overflow: hidden;
}

[aria-expanded] i {
  transition: transform 0.25s var(--ease);
}

[aria-expanded="true"] i {
  transform: rotate(180deg);
}

/* ---------- Papers ---------- */

.paper {
  display: grid;
  grid-template-columns: 11.75rem 1fr;
  gap: 1.75rem;
  padding-block: 1.5rem;
  border-top: 1px solid var(--line);
}

.paper:first-child {
  padding-top: 0.5rem;
  border-top: 0;
}

/* Figures keep their natural shape; a hover/teaser video sits exactly on top of the image. */
.paper-media {
  position: relative;
  align-self: start;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 0.625rem;
  background: #fff;
  transition: border-color 0.25s;
}

.paper:hover .paper-media {
  border-color: color-mix(in srgb, var(--ink) 30%, var(--line));
}

.paper-media img {
  display: block;
  width: 100%;
  height: auto;
}

.paper-media video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.paper-media video {
  opacity: 0;
  transition: opacity 0.3s;
}

.paper.is-playing video {
  opacity: 1;
}

.paper-title {
  margin: 0 0 0.5rem;
  color: var(--ink);
  font-size: 1.375rem;
  font-weight: 600;
  line-height: 1.35;
  letter-spacing: -0.01em;
}

.paper-title a {
  text-decoration: none;
}

.paper-authors {
  margin: 0 0 0.875rem;
  color: var(--muted);
  font-size: 1.09rem;
}

.paper-authors a {
  color: inherit;
  text-decoration: none;
}

.paper-authors a:hover {
  color: var(--accent);
}

.paper-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem;
}

.badge,
.chip {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  height: 1.75rem;
  padding: 0 0.625rem;
  border-radius: 0.375rem;
  font: 500 0.84rem/1 var(--font-mono);
}

.badge {
  margin-right: 0.25rem;
  background: color-mix(in srgb, var(--accent) 11%, transparent);
  color: var(--accent);
}

.chip {
  border: 1px solid var(--line);
  background: transparent;
  color: var(--text);
  text-decoration: none;
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s;
}

.chip:hover {
  border-color: var(--ink);
  color: var(--ink);
}

.chip[href]::after {
  content: "↗";
  color: var(--faint);
}

.chip i {
  color: var(--faint);
  font-size: 0.625rem;
}

.paper-tldr {
  margin: 0;
  padding-top: 0.875rem;
  font-size: 1.09rem;
}

/* ==========================================================================
   Responsive & motion preferences
   ========================================================================== */

@media (max-width: 1100px) {
  :root {
    --sidebar: 17.75rem;
    --gutter: 2.625rem;
  }

  .sidebar {
    padding-inline: 2.25rem 1.75rem;
  }

  .name {
    font-size: 2.25rem;
  }
}

/* Small screens: the sidebar becomes a compact header bar above the content. */
@media (max-width: 860px) {
  html {
    font-size: 100%;
  }

  :root {
    --gutter: 20px;
  }

  .layout {
    grid-template-columns: 1fr;
  }

  .sidebar {
    position: static;
    display: grid;
    grid-template-columns: auto 1fr auto;
    grid-template-areas:
      "portrait name toggle"
      "portrait links toggle";
    align-items: center;
    column-gap: 14px;
    height: auto;
    padding: 16px var(--gutter);
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  /* A small round crop centred on the face. */
  .portrait {
    grid-area: portrait;
    width: 76px;
    height: 76px;
    margin: 0;
    overflow: hidden;
    border-radius: 50%;
    mask-image: none;
  }

  .portrait img {
    width: 220%;
    max-width: none;
    margin: -14% 0 0 -54%;
  }

  .name {
    grid-area: name;
    margin: 0;
    font-size: clamp(1.25rem, 6vw, 1.75rem);
    white-space: nowrap;
  }

  .name > span {
    display: inline;
  }

  .profile-links {
    grid-area: links;
    flex-direction: row;
    gap: 2px;
    margin-left: -8px;
  }

  .profile-links a {
    justify-content: center;
    width: 34px;
    height: 34px;
  }

  /* Icons only; the labels stay available to screen readers. */
  .profile-links span {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
  }

  .theme-toggle {
    grid-area: toggle;
    width: 36px;
    height: 36px;
    margin: 0;
  }

  .content {
    padding-top: 28px;
  }

  .bio p {
    font-size: 1.15rem;
  }

  .section {
    padding-block: 28px;
  }

  .section-title {
    font-size: 2rem;
  }

  /* Dates sit above each item instead of in a side column. */
  .timeline-item {
    grid-template-columns: 1fr;
    gap: 2px;
    font-size: 1.09rem;
  }

  .text-button {
    margin-left: 0;
  }

  .paper {
    grid-template-columns: 1fr;
    gap: 18px;
  }

  .paper-media {
    justify-self: center;
    width: 70%;
  }

  .paper-title {
    font-size: 1.25rem;
  }
}

@media print {
  .sidebar {
    position: static;
    height: auto;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }

  html {
    scroll-behavior: auto;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}